Tray for loading sheets, including a receptacle and a lid having prevention means preventing the passage of sheets between the lid and the receptacle

ABSTRACT

A tray for a sheet processing apparatus has a receptacle (11), a lifting plate (12) movable between the low and high positions, arranged at the bottom of the receptacle and cooperating with an elastic thrust return member towards the high position, a lid (13) for covering the receptacle, and the tray has an arrangement preventing the passage of sheets between the cover and receptacle, having at least one clearance (44, 44&#39;) arranged on the periphery of the receptacle, and at least one plane limitation area (46, 46&#39;) arranged on the periphery of the lid and parallel to the bottom (37) of the receptacle, when the lid (13) is closed, the plane area (46, 46&#39;) being offset with respect to the internal surface of the lid and arranged on a support structure (48, 48&#39;) integral with the lid, this structure being positioned so that, in the closed position of the lid, it enters the said clearance (44, 44&#39;), the plane limitation area (46, 46&#39;) then opening onto the inside of the receptacle.

The present invention generally relates to a tray for loading sheetsinto a sheet processing apparatus.

As the sheet processing is situated downstream the loading tray in theapparatus, here by sheet "processing" will be understood:

the reading or the analysis of information borne by the sheets,

the formation of images on the sheets, for example by printing, and

more generally any use or transformation of the sheets by the processingdevice situated downstream the tray.

The present invention more particularly relates to a sheet loading trayfor an image forming apparatus such as a telecopier.

In the prior art there exist numerous sheet loading trays, intended forimage-forming apparatuses such as photocopiers, printers or telecopiers.

A known loading tray in particular has:

a bin, having an overall parallelepipedic shape and open at its upperface, intended to receive the sheets of paper;

a lifting plate arranged at the bottom of the bin and movable between alow position and a high position, this lifting plate being pivoted aboutan axis parallel with the bottom of the bin; and

a lid pivoted on the bin about an axis, movable between an open positionand a closed position, and arranged to cover, at least partially, thebin, this lid having to be removed in order to allow the loading of thesheets.

The lifting plate is suitable for cooperating with an elastic thrustmember tending to return it to its high position. According to themodels of trays and image-forming apparatuses, the elastic thrust membermay be integrated in the tray or integrated in the image formingapparatus and act on the lifting plate through an opening provided inthe bottom of the bin.

Such trays at present exist in several versions.

They are generally satisfactory with respect to their essentialfunction, i.e. storing the paper and allowing it to be fed sheet bysheet to the image forming apparatus.

However they have a certain number of drawbacks, which are essentiallyconnected with the fact that the sheet replenishing operation by theuser is not always easy.

First of all, once the sheets are placed in the bin, the user is forcedto manipulate it in order to introduce the tray into the image formingapparatus, at its location. A less careful user may, during thismanipulation, shake the tray so that the upper sheets of the piledisposed in the bin run the risk either of protruding beyond or ofescaping through the rear end, or of protruding beyond or escapingthrough one of the lateral edges. In this case, there is a risk of feedanomalies, because of the squeezing of the sheets between the lid andthe bin, resulting either in an absence of sheet feeding or, on thecontrary, in a feeding of two or more sheets at the same time. There isalso a risk of paper becoming jammed in the image forming apparatus.Furthermore, if the sheet is not correctly held between the lateraledges of the bin, it risks being grasped the wrong way by the imageforming apparatus, affecting the quality of the image formed on thesheet.

The present invention enables the above-mentioned drawbacks to beresolved.

Generally speaking, according to one of its aspects, the presentinvention proposes, for this purpose, a tray for loading sheets into asheet processing apparatus having a receptacle for containing the sheetsand a lid designed to cover the receptacle, said lid being movablebetween an open position and a closed position, characterised in that itincludes prevention means for preventing passage of the sheets containedin said receptacle between the receptacle and the lid at the closedposition.

Thanks to these provisions, in a general manner the sheets are preventedfrom protruding beyond or escaping through the peripheral junctionbetween the receptacle and the lid on the occasion of theabove-mentioned manipulation of the tray.

Preferably, the prevention means include at least one clearance arrangedon the periphery of the receptacle facing the lid, and at least oneplane limitation area arranged on the periphery of the lid and parallelto the bottom of the receptacle when the lid is closed, the planelimitation area being offset with respect to the internal surface of thelid and arranged on a support structure integral with the lid, thisstructure being positioned so that, in the closed position of the lid,it enters the said clearance, the said plane limitation area openingonto the inside of the receptacle.

In a preferred embodiment , the present invention proposes a tray forloading paper into a sheet processing apparatus having a receptacle, alifting plate movable between a low position and a high position,arranged at the bottom of the receptacle and suitable for cooperatingwith an elastic thrust member tending to return it to the high position,a lid designed to cover the receptacle, characterised in that itincludes prevention means designed to prevent the passage of sheetsbetween the lid and the receptacle, these prevention means including atleast one clearance arranged on the periphery of the receptacle facingthe lid, and at least one plane limitation area arranged on theperiphery of the lid and parallel to the bottom of the receptacle whenthe lid is closed, the plane limitation area being offset with respectto the internal surface of the lid and arranged on a support structureintegral with the lid, this structure being positioned so that, in theclosed position of the lid, it enters the said clearance, the said planelimitation area opening onto the inside of the receptacle.

Preferably, when the receptacle and the lid have a front end and a rearend, the rear end of the receptacle has at least one rear clearance,while the rear end of the lid has at least one rear plane limitationarea.

Here, the possible movement of the sheets is limited, on the one hand,upwardly because of the rear plane limitation area. It is, on the otherhand, limited towards the rear by the inner rear end of the receptacle,advantageously formed by the rear wall of a bin. Thus during themanipulation of the tray, after loading the paper therein, the uppersheets are prevented from protruding beyond or escaping from the rearend.

Preferably, and in a similar manner, when the receptacle and the lidhave lateral edges, each of the lateral edges of the receptacle has atleast one lateral clearance while each of the lateral edges of the lidhas at least one lateral plane limitation area.

Here too, during the manipulation of the tray, after loading the papertherein, the upper sheets are prevented from protruding beyond orescaping from the sides.

In fact, the possible movement of the sheets is limited in the samemanner as has just been described for the rear end.

Risks of jamming and absence of feed are avoided and the sheet arrivesin the printing area, when it concerns an image forming apparatus, witha correct positioning, guaranteeing the quality of the printed image.

When the receptacle is advantageously formed by a bin, the clearance isa notch formed in a corresponding wall of the bin.

It will be noticed in other respects that, in the prior art, the sheetreloading operation is not simple as the user has to:

completely remove the lid of the bin,

estimate a maximum number of sheets of paper in a pile,

place them in the bin, taking care not to damage their corners,

refit the lid.

Moreover, the user is also forced, when placing paper in the tray, toexert a thrust on the lifting plate against an elastic thrust means.

The present invention moreover enables the above-mentioned drawbacks tobe removed and the paper loading operations to be simplified.

In fact, according to another aspect, a tray of the present invention asdefined above is characterised in that the lid is mounted on thereceptacle for pivoting about an axis between an open position and aclosed position, is integral with the receptacle and has at least onelimitation area arranged so that when the lid is in the open positionthe limitation area is at a predetermined distance from the bottom ofthe receptacle, corresponding to the maximum thickness of paper capableof being loaded into the tray.

In a preferred embodiment, the limitation area is formed by a ridge onthe lid arranged in the vicinity of the axis of this lid.

Thanks to these provisions, the present invention mitigates theabove-mentioned drawbacks.

Firstly, the user does not have to dismantle the lid. He only has toopen it to load the paper. Then, the limitation area, advantageouslyformed by the ridge, is automatically positioned when the lid is opened.The user thus has at his disposal a visual reference in order todetermine in a first time the height of the packet of sheets which hemay load into the receptacle, advantageously a bin. Moreover, thelimitation area, advantageously formed by the said ridge, also acts as alimiter which physically prevents the user from loading more paper thanthe tray can contain without having the feeding errors mentioned above.

Finally, after loading the sheets into the receptacle, the user now onlyhas to fold down the lid, which is an easier operation than refittingthe latter, as in the prior art.

According to yet another aspect, a tray of the present invention asdefined above, in which a lifting plate movable between a low positionand a high position is arranged at the bottom of the receptacle, adaptedto cooperate with an elastic thrust member tending to return it towardsthe high position and integrated in the tray, is characterised in thatthe lid is mounted on the receptacle for pivoting about an axis betweenan open position and a closed position, is integral with the receptacleand has at least one thrust area while the lifting plate has at leastone bearing area, the thrust area and the bearing area being arranged soas to cooperate together so that, when the lid moves into its openposition, the said thrust area pushes the lifting plate towards its lowposition, in opposition to the said elastic thrust member.

In a preferred embodiment of this aspect of the invention, the thrustarea is arranged at the end of an arm integral with the lid, while thebearing area is arranged on a lug integral with the lifting plate.

Thanks to these provisions, the opening of the lid enables the liftingplate to be automatically positioned in its low position, the receptaclethen being ready to receive its maximum load of sheets. It will be notedthat the user no longer has to exert any thrust on the lifting plateduring the paper loading operation.

The present invention also proposes an image forming apparatus,comprising a tray as defined above, feeding means for separating andfeeding the sheet from said tray, and printing means for printing animage to the sheet fed by said feeding means.

The characteristics and advantages of the present invention willmoreover become apparent from the following description with referenceto the attached drawings on which:

FIG. 1 is a diagrammatical front view illustrating a telecopier equippedwith a paper loading tray in accordance with the invention,

FIG. 2 is a perspective view with a partially cut-away portion of thetray illustrated in FIG. 1,

FIG. 3 is a front view in longitudinal section of the tray, the lidbeing illustrated in its open position,

FIG. 4 is a view corresponding to FIG. 3, the lid being illustrated inits closed position,

FIG. 5 is a view corresponding to FIG. 3, illustrating the tray loadedwith paper,

FIG. 6 is a perspective view of the tray with a partially cut-awayportion, the lid being illustrated in its closed position,

FIG. 6a is an enlargement of the inset Via of FIG. 6,

FIG. 7 is a partial sectional view along the plane VII of FIG. 6 andalong line VII--VII of FIG. 8,

FIG. 8 is a view along arrow VIII of FIG. 7,

FIG. 9 is a detailed view of the front left part of the interior of thebin of the tray, and

FIG. 10 is a sectional view along line X--X of FIG. 4, the lid beingrepresented separated from the bin.

According to the chosen embodiment represented in the figures, a tray 10in accordance with the invention is arranged in a telecopier representedunder the general reference 20. It will be noted that the telecopier isan image forming apparatus capable of receiving the tray 10. Other imageforming apparatuses such as printers and photocopiers may obviously besuitable, and also sheet processing apparatuses such as those specifiedabove.

The telecopier has, in the conventional manner, a support plate 21 fordocuments to be sent, a reading area diagrammatically shown underreference 22, a document printing area 23 and a support plate 24 fordocuments received.

The tray 10, which is intended to receive the paper on which thedocuments received will be printed, cooperates with a device 25 forseparating the sheets loaded into the tray and for transporting themtowards the printing area 23.

The device 25 has, in the conventional manner, a roller 26 for drivingand seizing the sheets loaded into the tray, the tray having, as will bedescribed below, elastic thrust means intended to bring the upper sheetof the pile of paper 70 loaded in the tray into contact with the roller26.

The device 25 also has sheet transport rollers 25a, 25b arrangeddownstream the roller 26.

The means 21-26 have a structure well known to the man skilled in theart and already used in telecopiers, the invention concerning in thisparticular case the tray 10. These means 21-26 will consequently not bedescribed in further detail here.

A preferred embodiment of a tray in accordance with the invention willnow be described with the assistance of FIGS. 1 to 10.

The tray illustrated comprises a bin 11 forming the receptacle intendedto enclose, firstly, various means of the invention and, secondly, tocontain the sheets of paper.

The tray 11 has an overall parallelepipedic shape, with its interiorspace being capable of receiving a pile 70 of paper of predeterminedformat (A4 format in this embodiment). The tray also has a lifting plate12 movable between a low position (FIGS. 2, 3 and 5) and a high position(FIGS. 1, 4 and 6).

In accordance with the invention, the lifting plate 12 is suitable forcooperating with an elastic thrust member tending to return it to thehigh position.

In the chosen embodiment represented, the elastic thrust member isintegrated with the tray and is present in the form of a coil spring 30.In other embodiments, it will be possible for the elastic thrust memberto be present in other forms and to be integrated with the image formingapparatus, the important point being that its arrangement enables it tocooperate with the lifting plate of the tray in accordance with theinvention, in order to return this plate to its high position.

In the chosen embodiment represented, the lifting plate 12 is mountedpivoted on the structure of the bin 11, and more particularly on itslongitudinal sides or longitudinal walls, with only one of these, side16, being visible in FIG. 2, because of the partially cut-away portionprovided so that the invention can be better understood.

More precisely, in this embodiment the plate has a front end 31 and arear end 32, the length of the plate here being substantially less thanthat of the sheets. At the level of the rear end 32, the plate 12 hastwo mounting lugs 33 arranged on each side of the plate and themselvesbearing a notch 35 each suitable for receiving a pivot 36 integral withthe side 16, the pivot 36 and the notch 35, arranged on either side ofthe lifting plate 12, producing the pivoting of said plate on the bin11.

In this embodiment, the spring 30 is arranged in the vicinity of thefront end 31 of the lifting plate, in order to be compressed betweensaid plate and the bottom 37 of the bin 11. It is held in place by meanswhich have not been represented on the figures in order to facilitatethe understanding thereof and which can easily be performed by a manskilled in the art.

A lid 13 is also hinged on the bin 11 about an axis 14 (FIGS. 2 and 3)and is intended to cover partially the bin. The means producing thisrotation in this embodiment will be described later, with the aid ofFIG. 9.

In the remaining description, for convenience the end of the tray withthe reference 38 will be designated as "front end" or "feeding end",while the end with the reference 39 will be designated as "rear end".

In accordance with the invention, the lid has at least one limitationarea 40 so that when the lifting plate is in the low position (FIGS. 2,3) and when the lid is in the open position (also FIGS. 2 and 3), thelimitation area 40 is at a predetermined distance d from the bottom 37corresponding to the maximum paper thickness 70 capable of being loadedinto the tray (FIG. 5).

As, in the low position, the lifting plate 12 comes to lie on the samelevel as the bottom 37, here this predetermined distance is also thatbetween the limitation area 40 and the lifting plate 12.

In the embodiment, and in accordance with another advantageouscharacteristic of the invention, the limitation area is formed by asimple ridge 41 of the lid arranged on the latter in the vicinity of theaxis of rotation 14.

In the chosen embodiment represented, the ridge 41 is arranged to have acontact surface 42 having a substantial width, so as not to damage thesheet on the top of the pile 70 (FIG. 5). The ridge 41 may, in otherembodiments, have another physical shape and be rounded, for example.Here it extends over the entire width of the lid.

In operation, the loading tray described here has proved to be morepractical during the sheet loading operations than that in the prior artgiven in the preamble.

In fact, first of all, in accordance with a characteristic of theinvention, in normal operation the lid 12 is integral with the bin,since in this particular case it is hinged on the latter. The user doesnot have to detach this lid as in the prior art. It is sufficient forhim to bring it into its open position (FIGS. 2 and 3) whichautomatically positions the ridge 41 (in this particular case thesurface 42) at the distance d above the bottom 37 or the lifting plate,when said plate is in the low position.

The user thus has a visual reference in order to determine the maximumpaper height. He only has to slide the pile 70 into the space left freebetween the lifting plate 12 and the surface 42, the lifting plate beingable to be kept in its low position either because of pressure exertedby the user, or automatically, by means of the arrangement which will bedescribed below.

It will be observed in particular that the limitation area acts as alimiter which physically prevents the user from loading more paper thanthe tray can contain.

After loading the sheets, the user now only has to fold down the lid,which for him is a simpler operation than the remounting of the lidwhich he had to perform with the trays of the prior art.

A second aspect of the invention advantageously used in the embodimentchosen and represented in the figures will now be described.

In accordance with this aspect of the invention, the rear end 39 of thebin 11 has at least one rear notch 44, forming a clearance, while therear end 45 of the lid 13 has at least one rear plane limitation area46, which is parallel to the bottom 37 of the bin (when the lid 13 isclosed), the plane area 46 being offset with respect to the innersurface 47 of the lid and arranged on a support structure 48 integralwith the latter. The support structure 48 is positioned so that in theclosed position of the lid 13 it enters the notch 44, the rear planelimitation area 46 then opening on the inside of the bin 11 (FIGS. 4 and7).

In this embodiment, the bin includes three notches at the rear end,while the lid has three support structures 48 for rear plane limitationareas 46, a single support structure and a single notch being entirelyrepresented on FIG. 2 (only half of the second notch-structure unitbeing represented, because of the partially cut-away portion of FIG. 2).In other respects it is recalled that with respect to the cut-awayplane, the bin 11 illustrated on FIG. 2 is symmetrical.

In the chosen embodiment represented, the support structure 48 is formedby a bulge having the shape illustrated on the figures. A slope 54 isprovided in front of the surface 46 in order to avoid damaging thecorners of the sheets. This bulge is set in the mass of the material ofthe lid.

FIG. 7 enables the function of the plane limitation area to beunderstood. On this FIG. 7 it is observed that when the lid 13 is in theclosed position the rear plane limitation area 46 is situated parallelto the bottom 37 of the bin. This surface 46 acts as an abutment surfaceon which the upper sheet of the pile 70 comes to bear, on the assumptionthat during the manipulation of the loaded tray, said tray is returned,the sheets then tending to fall on account of gravity.

Therefore the upper sheet can not move in the direction of the innersurface 47 of the lid 13.

In other respects, the fact of disposing the surface 46 on a structure48 so that this surface 46 is considerably offset with respect to theinner surface 47 of the lid enables, by providing the complementarynotches 44 on the rear end wall 51 of the bin, an interlocking of thesupport structures 48 with the wall 51 to be achieved, during theclosing of the lid 13. Thanks to this characteristic, the sheets, and inparticular the upper sheet of the pile 70, can not slide in the gap 53capable of existing between the inner face 47 of the lid 13 and the freeupper edge 52 of the wall 51 (see the partial cut-away portion on FIG. 6in which the gap in question bears the reference 53). In fact, if aplane abutment surface 46 considerably flattened with respect to theinner face 47 and "opening" onto the inside of the bin, as visible inparticular in FIG. 4, were not provided, the upper sheets of the pile 70would be capable of sliding in the gap 53 and, for example, of beingsqueezed between the inner face 47 and the free upper edge 52. Thiswould have the effect of preventing the upper sheet being driven fromthe pile by the roller 26. This second aspect of the inventionadvantageously allows this drawback to be removed.

This provision also allows certain cases of jamming to be avoided, whichhave been observed by the applicant. In fact, if the upper sheet of thepile 70 comes to enter the gap in question and to be squeezed, the driveroller 26 may entrain the second sheet towards the separation andtransport device 25, this sheet in turn driving the first sheet byfriction. The result of this is that two sheets are driven towards theprinting device 23.

Thus thanks to the invention, the user may manipulate the tray as soonas it is loaded without the fear of seeing certain sheets squeezed bythe lid with the above-mentioned drawbacks.

Similarly, a lateral plane limitation area 46' parallel to the bottom 37of the bin is also provided (when the lid 13 is closed). This lateralplane area 46' is also offset with respect to the inner surface 47 ofthe lid and arranged on a support structure 48' integral with thelatter. This support structure 48' is also positioned so that in theclosed position of the lid 13, it enters a lateral notch 44' acting as aclearance, the lateral plane limitation area 46' then opening on theinside of the bin 11.

In this embodiment, the bin has two notches of this type, each providedin a lateral wall or side 16 of the bin 11, while the lid has twosupport structures 48' for the lateral plane areas 46', a single lateralsupport structure and a single lateral notch being entirely representedon FIG. 2 (the other lateral notch-lateral structure unit not beingrepresented on the figures because of the sections and partiallycut-away portions featured on them). As for the rear support structure48, the lateral support structure 48' is also formed by a bulge havingthe form illustrated on the figures. A slope 54' is also provided infront of the surface 46'.

The functions of the lateral plane limitation area 46' and the lateralsupport structure 48' are the same as those given above for the rearplane limitation area-rear support structure unit. As already mentioned,the risks of jamming and of absence of feed in particular are avoided.

But furthermore, the top sheet of the pile is correctly held between thelateral walls of the bin 11, when it is driven and it has left the planerear limitation areas. In fact, as long as this upper sheet is onlygrasped by the roller 26, but not yet by the transport rollers 25a, 25b,a displacement of the rear of this sheet towards the one or the other ofthe walls of the bin 11 is always possible.

The sheet therefore arrives in the printing area with more precisepositioning, guaranteeing a better quality of printed image.

The unit of these notches 44, 44' and support structures 48, 48' formprevention means designed to prevent the passage of sheets between thelid and the bin, these notches and structures being arrangedrespectively on the periphery of the bin and of the lid.

A fourth aspect of the invention advantageously used in the chosenembodiment represented in the figures will now be described.

According to this aspect of the invention, particularly visible in FIGS.2 to 4, the lid 12 has at least one thrust area 55, while the liftingplate 12 has at least one bearing area 56, the thrust area and thebearing area being arranged so as to cooperate together so that, whenthe lid comes into its open position (FIGS. 2 and 3), the said thrustarea 55 pushes the lifting plate towards its low position (FIG. 3) inopposition to the elastic thrust member (the spring 30).

In the chosen embodiment represented, according to a preferredembodiment of this aspect of the invention, the area is arranged at theend of an arm 57 integral with the lid 13, while the bearing area 56 isarranged on a lug integral with the lifting plate. As can be seen onFIG. 4, the arm 57 bearing the thrust area is provided at the front endof the lid 13, on the side thereof (the lid 13 has two of these arms, asit is symmetrical with respect to the cut-away plane of FIG. 2).Similarly, the lug bearing the bearing area of the lifting plate isarranged on the side of the latter, two of these lugs being in realityprovided on either side of the lifting plate, in the vicinity of thefront end thereof.

As can be seen on the figures, the arm 57 is arranged on the lid 13 withrespect to the axis 14 so that during the opening movement, the thrustarea 55 provided at the end of the arm 57 comes into contact with thebearing area 56 and then pushes the lifting plate 12 towards the bottom37 of the bin, as illustrated in particular in FIGS. 2 and 3.

Thanks to this provision, the user no longer has to push the liftingplate 12 manually when loading the paper. He simply has to open the lid.

A fifth aspect of the present invention advantageously used in thechosen embodiment represented on the figures will now be described.

According to this aspect of the invention particularly visible in FIGS.6 and 6a, the bin 11 has two tabs 60 for holding the front corners 61 ofthe sheets 70. These tabs open onto the inside of the bin 11 and have aholding surface 62 arranged with respect to the lifting plate 12 atleast at the same distance as that between the limitation area 40 andthe bottom 37, here the lifting plate when it is in its low position,the said lid being open (FIGS. 3 and 5). On these figures, it can infact be noted that the distance d existing between the surface 42 andthe upper surface of the lifting plate 12 is less than the distance d'existing between the surface 62 and the lifting plate 12, when it is inits low position, the lid 13 being open.

The function of the holding tabs 60, and more precisely their holdingsurface 62, is as in the prior art, to hold the paper in the tray (FIGS.6 and 6a), in particular during the loading operations, at the feedingend of the tray. However, in contrast to the prior art, during thepositioning of the pile of paper 70 in the tray, there is no risk ofdamaging the front corners of certain sheets, since one only has toslide the sheets beneath the surface 42, without having to bend thecorners of the sheets. Furthermore, if the surface 62 is provided at adistance d' greater than the distance d, there is no risk during loadingof seeing certain upper sheets of the pile 70 coming to abut against thetabs 60 and the corners being damaged as a result.

FIG. 9 shows that a vertically oriented guide surface parallel to thelongitudinal axis of the tray is arranged directly below the holdingsurface 62 of each tab 60. On FIG. 9, which is a detailed view, thevertical guide surface bears the reference 65. Two of these surfaces areobviously provided, directly below each of the tabs 60, the guidesurfaces 65 being spaced by a distance substantially greater than thewidth of the sheets. They are preceded by an obliquely oriented guidesurface 64 having two functions:

firstly, to avoid the presence of a sharp limitation edge of the surface65 on which the sheets would be capable of coming to abut and sufferingdamage to their corners during their loading into the tray,

and, secondly, to finalise the alignment of the sheets, before theyenter the space existing between the two vertically oriented guidesurfaces.

The arrangement of the pivoting means of the lid 13 on the bin 11 usedin the preferred embodiment will now be described with the assistance ofFIGS. 9 and 10.

During the development of its new tray, the applicant was confrontedwith a problem. In fact, in FIGS. 2, 3 and 5 it is noted that when thelid is open, it is kept in this position by an oblique abutment 80, onwhich it rests over a very small portion of its length. Its rear end 45is at a fairly great distance from the pivoting axis 14, in the regionof the length of the sheets having to be loaded into the bin (roughly 29cm). There is therefore a large lever arm formed by the distance betweenthe rear end 45 of the lid and an upper ridge 81 forming the upper limitof the abutment 80. Consequently, if a force in the direction of arrow F(FIG. 3) is exerted in the vicinity of the rear end 45, it is capable ofexerting a large moment on the lid and the articulation at the level ofthe axis 14 is subject to a stress in the direction of arrow F'. If thearticulation at the level of axis 14 is rigid, the moment exerted by theforce F may have the result of breaking the lid, especially if it ismade of a relatively fine plexiglass plate which consequently isfragile. Such a situation may arrive if a less careful user opens thelid abruptly, with a tendency to drive the latter beyond the abutment80.

In order to mitigate this drawback reduce this difficulty, and generallyaccording to another aspect of the invention, the pivoting means areadapted to be separated automatically in the event of an impact ofpredetermined force exerted on the lid, the latter thereby beingdisconnected from the housing.

According to a preferred embodiment of this aspect of the invention,which is particularly advantageous in that it is simple and not verycostly to use, the means for pivoting the lid about the said axisincludes a pivot 90 arranged at each side of the lid 13 on a lateralelastic lug 91, the pivot 90 having a disengagement slope 92 orientedobliquely with respect to the axis of the pivot (cf. FIG. 10).

In a complementary manner, a cylindrical housing 93 having dimensionscomplementary to the pivot 90 is provided in the wall 16, on the innerside thereof, the cylindrical housing having the axis 14 as its axis.

On FIG. 10 it is noted that the slopes 92 arranged on the pivots oneither side of the lid are overall oriented towards one another and areat their closest in the vicinity of the lower end of the elastic lugs91.

In this particular case the slopes 92 have a double function:

to facilitate the snapping-in of the pivot 90 into the housing 93,

and to facilitate the disengagement of the pivot in the event of impactson the lid in the direction of the arrow F (FIG. 3). In fact it is seenthat the slopes 92 are substantially oriented in the direction of arrowF' (when the lid 13 is open) so as to facilitate the dismantling of thepivot means formed by the pivots 90 and housing 93 (direction of arrowF') in FIG. 3.

In the chosen embodiment represented on the figures, in accordance withanother characteristic of this aspect of the invention, a snapping-inslope 95 provided on the inner side of the wall 16 is provided directlyabove the cylindrical housing 93, in order to facilitate the snapping-inof the pivot 90 in the housing 93 by a guiding of this pivot and aregular flexion of the lug 91, and also the accidental dismantling ofthe pivoting means further to a shock on the lid.

Obviously one will be able to provide other embodiments for the pivotingmeans of the lid 13 on the bin 11 capable of becoming separated in theevent of impacts on the lid in the direction of arrow F of FIG. 3.

Of course the present invention is in no way restricted to the chosenembodiment on the figures but on the contrary includes all the variantswithin the scope of the person skilled in the art.

In particular it will be possible to replace the bin by any other typeof receptacle, for example a bottom from which protrude studs forretaining the sheets by their edges.

In other respects, if the lid is mounted on the bin at the rear endthereof, opposite the feeding end, the predetermined distance relativeto the limitation area will simply be that between this area and thebottom of the bin if the lifting plate does not extend as far as therear end of the bin.

We claim:
 1. A tray for loading sheets into a sheet processing apparatushaving a receptacle and a lid designed to cover the receptacle, whereinthe tray includes at least one clearance arranged on the periphery ofthe receptacle opposite the lid, and at least one plane limitation areaarranged on the periphery of the lid and opposite to the bottom of thereceptacle, when the lid is closed, each plane limitation area beingoffset with respect to the inner surface of the lid and arranged on asupport structure integral with the lid, this structure being positionedso as to enter the corresponding clearance in the closed position of thelid, each plane limitation area then opening onto the inside of thereceptacle, thereby preventing the passage of the sheets contained inthe receptacle between the lid and the receptacle.
 2. A tray accordingto claim 1, further comprising a lifting plate movable between a lowposition and a high position, arranged at the bottom of the receptacleand suitable for cooperating with an elastic thrust member tending toreturn the lifting plate to the high position.
 3. A tray according toclaim 1 or 2, wherein the receptacle and the lid have a front end and arear end, at least one rear clearance being on the rear end of thereceptacle and at least one rear plane limitation area being on the rearend of the lid.
 4. A tray according to claim 3, the receptacle and thelid having lateral edges, wherein each of the lateral edges of thereceptacle has at least one lateral clearance while each of the lateraledges of the lid has at least one lateral plane limitation area.
 5. Atray according to claim 4, wherein each of the lateral edges has onelateral clearance, and each of the lateral edges of the lid has onelateral plane limitation area, each lateral clearance and each lateralplane limitation area being arranged in the vicinity of the rear end. 6.A tray according to claim 2, in which said elastic thrust member isintegrated, and further comprising means for pivotally mounting the lidon the receptacle for pivoting about an axis, between an open positionand a closed position, wherein the lid is integral with the receptacleand has at least one thrust area while the lifting plate has at leastone bearing area, each thrust area and each bearing area being arrangedso as to cooperate together so that, when the lid moves into its openposition, each thrust area pushes the lifting plate towards its lowposition, in opposition to the corresponding elastic thrust member.
 7. Atray according to claim 6, wherein each thrust area is arranged at theend of an arm integral with the lid and each bearing area is arranged ona lug integral with the lifting plate.
 8. A tray according to claim 6,wherein the means for pivotally mounting the lid on the receptacle areadapted to be automatically separated in the event of an impact ofpredetermined force exerted on the lid, the latter thereby beingdisconnected from the receptacle.
 9. A tray according to claim 2,further comprising means for pivotally mounting the lid on thereceptacle for pivoting about an axis between an open position and aclosed position, wherein the lid is integral with the receptacle and hasat least one limitation area arranged so that when the lid is in theopen position each limitation area is at a predetermined distance fromthe bottom, corresponding to the maximum thickness of paper that can beloaded into the tray.
 10. A tray according to claim 9, wherein eachlimitation area is formed by a ridge on the lid arranged in the vicinityof the pivoting axis of the lid.
 11. A tray according to any one ofclaims 9 and 10, wherein the receptacle has a front end, and has twotabs for holding the front corners of the sheets, these tabs openingonto the inside of the receptacle and having a holding surface arrangedwith respect to the lifting plate, when the latter is in the lowposition, at a distance from the latter that is equal to or greater thanthat which exists between each limitation area and the bottom, the lidbeing open.
 12. A tray according to claim 11, wherein the receptacle isa bin having a sheet guide surface directly below each of the tabs andan obliquely oriented sheet guide surface, preceding said sheet guidesurface directly below the tabs.
 13. A tray according to claim 1,wherein the receptacle is a bin, and said at least one clearance is anotch formed in a corresponding wall of the bin.
 14. A tray according toclaim 1, characterised by a pivot arranged on each side of the lid on alateral elastic lug for pivotally mounting the lid on the receptacle, adisengagement slope arranged on the pivot and oriented obliquely withrespect to the axis of the pivot, a cylindrical housing for each pivot,formed in the lateral wall of a bin forming the receptacle, the axis ofthe cylindrical housing being collinear with the axis about which thelid pivots.
 15. A tray according to claim 14, wherein a snapping-inslope, oriented in the desired direction of mounting of the lid, isarranged directly above the cylindrical housing.
 16. An image formingapparatus, comprising:a tray having a receptacle and a lid designed tocover the receptacle, wherein the tray includes at least one clearancearranged on the periphery of the receptacle opposite the lid, and atleast one plane limitation area arranged on the periphery of the lid andopposite to the bottom of the receptacle, when the lid is closed, eachplane limitation area being offset with respect to the inner surface ofthe lid and arranged on a support structure integral with the lid, thisstructure being positioned so as to enter the corresponding clearance inthe closed position of the lid, each plane limitation area then openingonto the inside of the receptacle, thereby preventing the passage of thesheets contained in the receptacle between the lid and the receptacle,feeding means for separating and feeding a sheet from said tray, andprinting means for printing an image to the sheet fed by said feedingmeans.
 17. An apparatus according to claim 16, wherein the tray furthercomprises a lifting plate movable between a low position and a highposition, arranged at the bottom of the receptacle and suitable forcooperating with an elastic thrust member tending to return the liftingplate to the high position.
 18. An apparatus according to claim 16 or17, wherein the receptacle and the lid have a front end and a rear end,the rear end of the receptacle having at least one rear clearance andthe rear end of the lid having at least one rear plane limitation area.19. An apparatus according to claim 18, the receptacle and the lidhaving lateral edges, wherein each of the lateral edges of thereceptacle has at least one lateral clearance while each of the lateraledges of the lid has at least one lateral plane limitation area.
 20. Anapparatus according to claim 19, wherein each of the lateral edges has alateral clearance and each of the lateral edges of the lid has a lateralplane limitation area, each lateral clearance and each lateral planelimitation area being arranged in the vicinity of the rear end.
 21. Anapparatus according to claim 17, wherein the thrust member is integratedin the tray, the tray further comprises means for pivotally mounting thelid on the receptacle for pivoting about an axis, between an openposition and a closed position and wherein the lid is integral with thereceptacle and has at least one thrust area while the lifting plate hasat least one bearing area, each thrust area and each bearing area beingarranged so as to cooperate together so that, when the lid moves intoits open position, each thrust area pushes the lifting plate towards itslow position, in opposition to the corresponding elastic thrust member.22. An apparatus according to claim 21, wherein each thrust area isarranged at the end of an arm integral with the lid and each bearingarea is arranged on a lug integral with the lifting plate.
 23. Anapparatus according to claim 21 or 22, wherein the means for pivotallymounting the lid on the receptacle area adapted to be automaticallyseparated in the event of an impact of predetermined force exerted onthe lid, the latter thereby being disconnected from the receptacle. 24.An apparatus according to claim 17, wherein the tray further comprisesmeans for pivotally mounting the lid on the receptacle for pivotingabout an axis between an open position and a closed position, andwherein the lid is integral with the receptacle and has at least onelimitation area arranged so that when the lid is in the open positioneach limitation area is at a predetermined distance from the bottom,corresponding to the maximum thickness of paper that can be loaded intothe tray.
 25. An apparatus according to claim 24, wherein eachlimitation area is formed by a ridge on the lid arranged in the vicinityof the pivoting axis of the lid.
 26. An apparatus according to claim 24or 25, wherein the receptacle has a front end and wherein the receptaclehas two tabs for holding the front corners of the sheets, the tabsopening onto the inside of the receptacle and having a holding surfacearranged with respect to the lifting plate, when the latter is in thelow position, at a distance from the latter that is equal to or greaterthan that which exists between each limitation area and the bottom, thelid being open.
 27. An apparatus according to claim 26, wherein thereceptacle is a bin having a sheet guide surface directly below each ofthe tabs and an obliquely oriented sheet guide surface, preceding saidsheet guide surface directly below the tabs.
 28. An apparatus accordingto claim 16, wherein the receptacle is a bin, and said at least oneclearance is a notch formed in a corresponding wall of the bin.
 29. Anapparatus according to claim 16, further comprising a pivot arranged oneach side of the lid on a lateral elastic lug, for pivotally mountingthe lid on the receptacle, a disengagement slope arranged on the pivotand oriented obliquely with respect to the axis of the pivot, acylindrical housing for each pivot, formed in the lateral wall of a binforming the receptacle, the axis of the cylindrical housing beingcollinear with the axis about which the lid pivots.
 30. An apparatusaccording to claim 29, wherein a snapping-in slope, oriented in thedesired direction of mounting of the lid, is arranged directly above thecylindrical housing.